The present invention concerns an electric timepiece such as, in particular, a wristwatch, supplied with electric current by an accumulator which is intended to be recharged once flat, and means for recharging the accumulator.
There is known from Swiss Patent No. 345 611 a watch including a recharging terminal passing through the watch case, this terminal being electrically insulated from said case. The end of the terminal situated inside the case is electrically connected to one of the poles of the accumulator intended to supply the watch with electric current, while the end of the terminal situated outside the case is fitted with a removable protective cap, this cap also being electrically insulated from said terminal.
More precisely, the accumulator recharging device disclosed in the aforementioned Patent includes a metal stem passing through a sleeve made of an electrically insulating material, this sleeve itself being housed in a second reinforcing sleeve. This latter sleeve, which is metallic, is driven into the middle part of the watch case. The inner end of the stem is in contact with the top face of the accumulator which forms one of the poles of said accumulator, while the outer end of said stem is pierced with a blind hole intended to accommodate the plug of a recharging apparatus. In normal operating conditions of the watch, the outer end of the stem is protected by a removable cap having the shape of a winding crown.
Recharging of the accumulator can be effected by means of a pocket torch battery. The recharging apparatus includes two metal strips electrically insulated from each other. One of the strips carries a conical plug intended to penetrate the blind hole of the recharging stem described above. The other strip of the recharging apparatus is in contact with the earth of the watch, for example with the time-setting crown. The battery thus recharges the accumulator, one night being generally sufficient for the accumulator to be able to power the movement again for several months.
Such a recharging device advantageously permits the accumulator supplying a watch with electric current to be recharged without it being necessary, in order to proceed with this recharging operation, to open and then close the watch case again in order to be able to remove then replace the accumulator in said case. One can thus recharge the accumulator arranged inside the watch case from the outside of said case.
Such a recharging device has however certain drawbacks from among which one can cite the fact that it is necessary to provide an additional part, in this case a recharging stem, solely intended to allow the watch accumulator to be recharged. This additional part considerably complicates the construction of the watch case which, of course, has a negative impact on the manufacturing costs. The recharging stem which passes through the watch case also has the drawback of altering the sealing or water tightness thereof. Finally, it should also be pointed out that the recharging stem and the time-setting crown by means of which the accumulator is recharged, are in permanent electric contact with said accumulator. Thus, unless complex and expensive arrangements are provided to electrically insulate the recharging stem and the time-setting crown from the rest of the case, there is a risk of the accumulator inadvertently being discharged in the event that the watch becomes wet or simply damp from the perspiration of its wearer.
The object of the present invention is to overcome the above problems and drawbacks in addition to others by proposing a particularly simple and inexpensive system for recharging the accumulator of a watch.
The present invention therefore concerns a timepiece, in particular a wristwatch, supplied with electric current by an accumulator intended to be recharged once flat, this timepiece including a time-setting stem and at least one control member for at least one horological function of said timepiece, characterised in that the time-setting stem is electrically connected to one of the poles of the accumulator, and in that the control member can be electrically connected to the other pole of the accumulator after said member has been pressed.
According to another embodiment, the present invention also concerns a timepiece of the aforementioned type, this timepiece including at least a first and a second control member each controlling at least one horological function of said timepiece, characterised in that each of the first and second control members can be connected to one of the poles of the accumulator after said member has been pressed.
As a result of these features, the watch accumulator can be recharged solely by using the means carried by the watch for adjusting and activating its usual horological functions. It is thus no longer necessary to add additional parts to the watch such as a contact stem or suchlike to be able to connect the accumulator of said watch to a recharging apparatus. The construction of the watch is thus simplified, which substantially limits the manufacturing costs. Likewise, the sealing of the case is not altered.
According to a complementary feature of the invention, the control member or members are push-buttons.
As a result of this other feature, the accumulator charging circuit is only closed when the push-button or push-buttons are pushed in, which avoids any risk of the accumulator being inadvertently discharged when the watch is not placed on the recharging apparatus. It should be noted, on the other hand, that it is very convenient to use the push-buttons as electric contact parts between the accumulator and the charger. These push-buttons may, in fact, be easily insulated from a metal case insofar as they do not engage or mesh with the movement of the watch but act by simple electric contact, for example with a printed circuit contact area, to control the horological functions of said watch.